Easy-open can ends are well known in the field of can manufacture—for example, that described and shown in FIGS. 4 & 5 of U.S. Pat. No. 5,413,241 (YEH HSI-SHOU) Sep. 5, 1995, and also DE 2540362. The can end is provided with an end panel provided with a score line defining a prearranged opening area. A tab is secured to the end panel, with the nose of the tab located adjacent the score line. To avoid interference between adjacent can ends during transportation of the can ends themselves, the handle of the tab is located against the outer surface of the end panel. It would remain in this position after attachment of the can end to a can body—as is normal practice for virtually all current easy-open can ends. However, this presents a problem for a consumer wishing to open the can because the consumer must first prise the handle of the tab away from the surface of the end panel in order to lift the tab to rupture the score line. The lack of clearance between the tab handle and the end panel makes this an arduous task, especially for those with weak hands.
WO 03/104092 A (MAEIL DAIRY INDUSTRY CO LTD) Dec. 18, 2003 provides one solution to the above problem of tab access. WO 03/104092A discloses a can end having a collapsible protrusion under the handle of the tab. The collapsible protrusion initially protrudes upward from the can end to define a minimal (or zero) gap between the tab and the protrusion (providing efficient stackability of one can end upon another for storage/transportation purposes), but is deformable downwards from the tab to define a concave finger well under the handle of the tab sufficient for a user to insert their finger (providing finger access under the tab and ease of opening by a consumer).
However, there are several problems with the protrusion shown and described in WO 03/104092A:                Firstly, the collapsible protrusion of WO 03/104092A has to occupy a substantial area of the can end in order to define a finger well of sufficient depth to permit a consumer to insert their finger under the tab.        Secondly, when containers incorporating the can end of WO 03/104092A are exposed to positive pressure (i.e. where the pressure within the container is greater than that outside), the protrusion can easily revert into its upward state, thereby removing any clearance under the tab and hindering tab access. Positive pressure may arise due to the environment in which containers incorporating the can end are stored, or due to the nature of the product stored within the container. For example, carbonated beverage products provide continual positive pressure. Alternatively, certain food products may expel gases during their storage. Additionally, the heating from retort processing can result in a build-up of positive pressure within the container.        Thirdly, the protrusion of WO 03/104092A is a non-planar surface, which can present a difficult surface on which to print logos, images or instructions.        
There is therefore a need to have an improved can end which:    i. maximises the area of the can end suitable for printing;    ii. is easily stackable for efficient storage/transportation, without risk of the can end becoming trapped between the tab and end panel of an adjacent can end;    iii. is also able to provide and retain tab access to enable a consumer to easily lift the tab (even when subject to positive pressure during use on a container).